Maybe I'm missing something here--YOU wanted to buy the gym, but YOU decided not to do it. This is OK.

But HE decided not to run the gym anymore, and this is NOT OK. In fact, this makes him a DICK and the emblem of (and spokesman for) his entire generation, who are ALSO DICKS.

All because a guy who owns a gym decided to close it, forgetting that HE OWES YOU A GYM.

Do you notice that somewhere in there you become the jerk in this story? It's his fucking gym. If he wants to close it, that's his call, NOT yours. It's not your property.
Why exactly does this guy owe you so much, and how come you don't owe him anything?